Method of making nonwoven fabric



Feb. 23, 1954 y D, K, RlDER 2,670,315

METHOD OF MAKING NONWOVEN FABRIC Filed March 3l, 1949 T13-5- TIE' l l m# tu;

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ATTORNEY Patented Feb. 23, 1954 METHOD OF` MAKING N ONWOVEN FABRIC Don K. Rider, Plainfield, N. J., assigner to Chicopee Manufacturing Corporation, a corporation of Massachusetts v Application March 31, 1949, Serial No. 8d,637

This invention relates to cloth of novel construction and to methods of making it. It is particularly concerned with non-woven fabrics made of the usual textile fibers, by which is meant any fibers suitable to be spun and woven into cloth. Cotton and rayon are prominent examples.

Textile fibers are distinguished esp-ecially by their length from other similar but shorter fibers, for example those used in making paper. In fact in some instances identical fibers may be classed as textile fibers or not depending on their length. Therefore as used herein the term textile fibers designates bers suitable for spinning and weaving into cloth by the customary methods of making cloth and the term textile fabric or textile cloth designates fabric sheet made from such textile fibers Whether or not the fabric is Woven, knitted, felted or otherwise made.

One of the objects of the invention includes the making of an improved teztile fabric in which one of its surfaces has markedly different Wettability by water and aqueous adhesives. This aspect of the invention is applicable to filters and to wall coverings, especially to foundation materials to which wallpaper is applied. This embodiment of the invention will be described for the sake of example in connection with such foundation materials.

Other objects and advantages of the invention will beevident in the accompanying description and accompanying drawings.

In the drawings Fig. 1 is a plan of one form of fabric embodying the invention;

Fig. 2 is an enlarged fragmentary section on the line Z--E of Fig. l, the section being taken along a bonding stripe;

Fig. 3 is an enlarged fragmentary section on the line 3-3 of Fig. l taken between bonding stripes;

Fig. 4 is an enlarged section of a portion of a wall covered with our improved fabric as a foundation for wallpaper; and

Figure 5 is an enlarged section of a portion of .a wall covered with my improved fabric as a foundation for wallpaper showing the Wallpaper partially stripped away from the wall and the point of rupturing of the laminated layer.

In the Goldman Patent 2,039,312 there is described a non-woven textile fabric formed by superposing carded webs of cotton and binding the fibers together by adhesive material printed or pressed through the webs along separated lines. In the patent to Besso and Habicbt 1,532,648 there is described a non-woven textile 3 Claims. (Cl. 154-122) fabric formed by disposing cotton fibers completely at random in an air stream, gathering them on a screen, and suitably binding the fibers, for example by solvent applied at spaced points. In either an ordinary carded web, or a Besso and Habicht web, the fibers or at least a substantial proportion of them are what I call polyposed, by which is meant that the fibers are arranged at random or in many positions, without order or system. This is true in usual carded Webs, for although one of the objects of carding is to align the fibers in parallel, complete alignment is not usually achieved. In fact that appropriate settings of the carding machine, and sufficient speed of operation a very high degree of random arrangement can be had. ThusvI use the term polyposed to refer tothe disordered arrangement of fibers in either a card web or a web of the Besso and Habicht type. In webs of polyposed fibers made by either process there is also a con.- siderable entanglement of the fibers, which aids in holding the fibers together. i

In making my improved fabric I form in any suitable manner a foundation ID of fibers which are readily wettable by water and by particular adhesives, such as starch paste or polyvinyl acetate emulsions. I secure to a face of this foundation a non-woven layer l2 of bers of a dierent character, that is they are less wettable by water and such adhesives. Preferably both the foundation l0 and the layer l2 are non-woven webs of polyposed fibers. The bers in each web are entangled, and preferably the two webs are joined face-to-face by entanglement of the bers of one web in the fibers of the other. These two webs are then bonded together by any suitable adhesive printed on or into the webs, preferably along separated lines, for example the lines in the diamond grid pattern i4 of Fig. l.

The difference in the wettability of the bers may vary widely depending on the characteristics desired in the final fabric and, in fact, the fibers in the web l2 may be practically non-wettable by Water or by particular adhesives. As one example, the web It may be formed of one or more carded webs of rayon or absorbent cotton such as bleached cotton. The web I2 may be formed of one or more layers of non-absorbent cotton, such as unbleached cotton. The adhesive may be a water emulsion of polyvinyl acetate. The adhesive is ordinarily applied by passing the webs between any suitable printing roll and backing roll (not shown) such as is described by Goldman, the printing roll being in contact with the web formed of wettable iibers so as to apply the adhesive rst to the wettable web and then pressing it through this into the less Wetable web. In order to apply the binder adhesive to both kinds of fibers it may be necessary to render all fibers temporarily Wettable by the binder by wetting out the Webs with a solution of an appropriate known wetting agent just before applying thefadhesiye.

After-l the binder is applied the web isy dried in any usual manner, for example by passing the fabric over heated drying cans. This reduces the effectiveness of the wetting agent. as, regards re-wetting of the Web, either by reducing its quantity or inactivating it, thus'p1todncingaz..fahric having one side relativelyrwettablebyeadhosives such as starch paste, and one side relatively less wettable by the paste,... Thiais particu:4`

larly useful for a foundation fabric for Wallpaper, the surface next to the wall being wettable by.

such paste in order that this surface may be stronglya bonded; to. thee wall; while the other sur face: bebonded-.to thewallpaper by.: a. weak-fen, but: adequate bend Referring toFis.. a. t@ desig-natesthesuriaoe of; ai wall., whichy mayv be Wood. composition boardV or the like. The: composite fabric above' described` is: applied to this surface. either by taclringgatintervals or. by any suitable adhesive suon as starch paste1 which.A forms; a1 relatively permanentbondiandwhch .is not readily softened by subsequent application of the adhesive. on- .the wallpaper.- Th'e Wettable side.- of the fabric is applied to, the. surface l-,Er and the. less; Wette-ble sida is.; away: from. thefwall. Wallpaper. repre.- sentedv bythe-layer t8.r mais7 then be applied by pasting" totI the less. Wettablef side of. fabric, in1 the manner that. paper isv customarily pasted walls;

'Ihe materialihas; the advantage that thawallpapel? adheres; tcthafabricand thus: to tha milyfenough to. stay in place.- asi long;` as. desired but the fabric enablesathe paper to;- b e-.strip.ped readily from thefwall Whenitis desiredztofrenaper themfalh. Whenever itis desired tofstrinthewallr paper, an edge orcornery of. themaper isapried loosefronrtlievvallbyl knifeonspatula and1 using thisY loosened edge: asaholdl. thefpaper can be readily.x stripped, Without soaking; orf` softening; of

the pasta.

The.3 abilitato; strip tha paper; isbelievzed. to,- be

duct both. to. therlowfwettabilityf of the surface layenzandi to.' the relativelyy` wealsbonding;l of. the tofthisiayexv. Theflow'wettability permits limited absorption of the wallpaper paste and prevents the paste from reaching the wettable layer thus preventing the paper from being bonded to the wettable layer. In many instances the ability to strip is also believed to be due to the poor adhesion of the binder to the less Wettable fibers in the manufacture of the fabric.

The invention; olaimedlis;

1. The method of making fabric which comprises assembling a layer of relatively wettable bers and a second layer of less wettable textile fibers.. rendering-I the second layer temporarily wettable by applying an aqueous dispersion of aiwet-tingfagent, saturating binding areas of both Y layers with arr aqueous adhesive and evaporating theewaterinthc'dispersion of the wetting agent toipnovide, ai. fabric having a relatively Wettable layer of fibers on one surface and a layer of less 'vvett'ablev fibers on the other surface.

2. The method of making non-woven fabric haffingone :relatively wettable surfaces. andi one relatively lessl wettable surface which; comprises assembling a: layer of readily;v Wettaiole textile berswith ala-yer. of;v less readily Wett-able textile bers.;.saturating theyassemblywith; a water dis;- persion; of: an: adhesiva byapplying; the-:adhesive first to the readily Wettable layer and thenxre..i moving the: water v toaleavea the.- adhesive.

3; The; method of' making. nonfwovemfabrie having one relatively,l wettablef surface and one relatively lless wettable; surface: which.4 comprises assembling4 a. layer of readily' wettable textile berswith ai layer. of less: readilyvvettablel textile fibers; saturating the assembly`- with,` a. water `disvpersiorrof an, adhesive. by rst applying thefadhef siveto theareadly wettableflayer'and thento: the less readily Wettable layer and removing; the Water f tleava the: adhesive.

References sited.. inV the. sie or. this patent.

STATES' PATENTS.;

Number Name Date 1,558,495.. Qverbury Oct. 2T, 1925 l.-,8.65;23. Bronson; June 28,1932 1,361,365 Jones et. all June-.5;,1934 2,03%312 Goldman May 5;,1936 2,084,796 Dwight June 22, 193,7 .2,232,645 Zirkmamw. ....E'eb 18,..l'941 ZLSHfLfL. Knowl'and Mar. 23, 19.43 2,429,314 Goldman. @c t. 2'1", 1947 2,95ll86- Eerguson 0ct. 5', 1948 

1. THE METHOD OF MAKING FABRIC WHICH COMPRISES ASSEMBLING A LAYER OF RELATIVELY WETTABLE FIBERS AND A SECOND LAYER OF LESS WETTABLE TEXTILE FIBERS, RENDERING THE SECOND LAYER TEMPORARILY WETTABLE BY APPLYING AN AQUEOUS DISPERSION OF A WETTING AGENT, SATURATING BINDING AREAS OF BOTH LAYERS WITH AN AQUEOUS ADHESIVE AND EVAPORATING THE WATER IN THE DISPERSION OF THE WETTING AGENT TO PROVIDE A FABRIC HAVING A RELATIIVELY WETTABLE LAYER OF FIBERS ON ONE SURFACE AND A LAYER OF LESS WETTABLE FIBERS ON THE OTHER SURFACE. 